In the last years real-time visualisation with virtual reality techniques has become to an essential part of numerical simulation in almost all major fields of engineering. This circumstance causes a high percentage of users, having only a basic or no experience in the handling of such systems. Especially in traditional fields of technology like tunnelling the technical staff, researchers or other involved persons are not familiar with the navigation in a virtual environment. An excellent visualisation of the available data that can be used very easy has been shown as absolutely necessary to sell the technology of numerical simulation. The navigation is a central part of the usability of a visualisation tool. We describe the improvements of the navigation of the "Tunnelling Visualisation System -TVS" [Opriessnig, G., (1999)][Opriessnig, G. et al., (2001)] which are collision detection and several modifications of mapping the user input to the virtual reality scene. The reason for these modifications is the improvement of the systems user-friendliness by making the navigation more realistic and exact.